Device for handling bagged or bundled soft material

ABSTRACT

Article transporting apparatus with an articulated two section boom assembly connected at one end to a movable base, for example, a wheeled vehicle to allow rotation of the boom assembly about a vertical axis as well as vertical pivotal movement. A gripper assembly including a pair of swinging gripper arms is pivotally connected at the free end of the boom assembly. A parallel motion control system maintains a a predetermined attitude of the gripper assembly during vertical pivotal movement of the boom assembly. The gripper arms are especially adapted for grasping material subject to tearing, for example, a burlap sheet containing bundled material.

United States Patent 1191 Pinkham et a1. Aug. 14, 1973 [54] DEVICE FOR HANDLING BAGGED ()R 3,179,137 4/1965 Kilner 294/106 X BUNDLED SOFT MATERIAL 3,587,888 6/1971 Warren 214/147 R X [75] Inventors: Douglas Primary Examiner-Gerald M. Forlenza P Sal Assistant Examiner-George F. Abraham z h all?! C Attorney-Stepno & Neilan [73] Assignee: Reynolds, R. J., Tobacco Company, [57] ABSTRACT wmston'salem' Article transporting apparatus with an articulated two [22] Filed; Au 20, 1971 section boom assembly connected at one end to a movable base, for example, a wheeled vehicle to allow rota- [21] Appl' 173498 tion of the boom assembly about a vertical axis as well as vertical pivotal movement. A gripper assembly in- 521 US. Cl. 214/147 0, 214/138 R eluding a P of swinging gripper arms is Pivotally 51 1111. C1. B66c 1/42 nected at the free end of the boom assembly- A Parallel 581 Field of Search 214/147 G, 147 R, motion control System maintains a a predetermined 214/1 BD' 1 CM; 294/10 titude of the gripper assembly during vertical pivotal movement of the boom assembly. The gripper arms are 56] References Ci d especially adapted for grasping material subject to tear- UNITED STATES PATENTS ing, for example, a burlap sheet containing bundled 3,630,389 12/1971 Schmidt 214/147 R mammal- 3,147,993 9/1964 Broderson 294/106 X 6 Claims, 5 Drawing Figures Patented Aug. 14, 1973 3,752,337

3 Shae ts-Sheet 1 N I k INv TORS JESSE R. PINK'H DOUG C. CL

DONA R. W NSON mum . 4 ATTORNEYS Patented Aug. 14, 1973 3 Sheets-Sheet 2 INVENTORS JESSE R. PINKHAM DOUGLAS 0. CLARKE DONALD R. WILKINSON Wren! k-Z n- ATTORNEYS Patented Aug. 14, 1973 3,752,331

3 Sheets-Sheet 3 INVENTORS JESSE R. PINKHAM DOUGLAS C. CLARKE DONALD R. WILKINSON @WLW ATTORNEYS DEVICE FOR HANDLING BAGGED OR BUNDLED SOFT MATERIAL BACKGROUND OF THE INVENTION The present invention relates to article handling apparatus, and more particularly to apparatus for grasping an article utilizing a gripper assembly at one end of an articulated boom assembly and transporting the article to another position where the article is released.

Although not limited thereto, the invention is especially adapted for handling bagged or bundled soft material where there is a tendency for a conventional article handling structure to tear or damage the enclosing material of the bag or bundle and/or the enclosed material. An especially useful function of the apparatus of the invention is to transport leaf tobacco which is tied up in burlap sheets.

Leaf tobacco is marketed at auction sales in lots of tobacco weighing an average of 160 pounds per lot and not exceeding 200 pounds. These lots, which may be of many different grades, are approximately 4 feet in diameter and up to 2% feet high. The pile of tobacco is centered on a rectangular sheet of burlap about 7 feet square. When the lot of tobacco is sold, the four corners of the burlap sheet are brought up and around the pile and tied at the top into a square knot. Handling this mass is very difficult in view of its weight and because the mass is soft and shifty making it difficult to grasp manually. Due to its size and awkwardness, it is conventional practice to move these bundles manually employing two men for the task. However, this is a short seasonal job and it is becoming increasingly difficult to obtain and retain help for this task. If subsequently the bundled tobacco is stacked, it is even more difficult to remove the upper bundles manually.

Mechanical lifting of these bundles employing known apparatus is difficult particularly from a nested or bulk stored position because the bundles which are referred to in the trade as sheets blend and nest together so that it is necessary to get a hold of and lift the load from above rather than get under the load and lift by conventional means. Hooks are not a satisfactory approach to this problem since unlessthe hooks are meticulously placed through the two knots by hand, they will tend to tear the sheet.

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide a novel apparatus for the handling and transporting of bagged or bundled soft material.

Another object of the present invention is to provide an improved article handling apparatus which includes a novel pivotally positioned gripper assembly disposed at the free end of an articulated boom assembly.

According to a presently preferred embodiment of the invention, an articulated two section boom assembly is mounted upon a movable base, for example, the rear of a fork truck or other vehicle. The first section of the boom assembly is comprised of a pair of spaced parallel beams which are pivotally connected to a pivot block to enable pivotal movement of the boom assembly in a vertical direction relative to the vehicle. The pivot block and the boom assembly is rotatable about a vertical spindle on the vehicle via a hydraulic motor. A hydraulic cylinder having one end secured to the pivot block and having the free end of its piston arm secured to a block which is connected approximately to the mid points of the two parallel beams adjusts the vertical position of the first section of the boom assembly. The second section of the boom assembly comprises a beam which is pinned between the outer ends of the parallel beams of the first section and is pivoted by means of another hydraulic cylinder. A gripper assembly is pinned to the free end of the second boom section and its attitude relative thereto is adjusted via a parallel motion system which includes sprockets and chains disposed within the second beam section to which motion is imparted via an endless chain which is disposed between the two parallel beams of the first section and which has its lower end trained about a sprocket upon an axle in the pivot block. A third hydraulic cylinder rotates the sprocket at the pivot block through an are sufficient to provide the desired adjustment of the gripper assembly regardless of the relative positions of the two boom sections.

The gripper assembly includes a pair of hydraulically actuated gripper arms which are mechanically interconnected via gear segments so that the arms move in unison into and out of the article engaging position. The article engaging surfaces of the arms are preferably covered with rubber having a treaded surface in order to minimize the possibility of tearing the article while providing a surface capable of achieving a finn grip upon the article.

The above and other objects, features and advantages of the present invention become more apparent as this description proceeds.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a presently preferred embodiment of the present invention.

FIG. 2 is a partial plan view illustrating the connection of the boom assembly to the vehicle.

FIG. 3 is a vertical cross-sectional view taken on the line 33 of FIG. 2.

FIG. 4 is a view primarily in vertical cross-section of a portion of the apparatus of FIG. 1 showing the apparatus for rotating the gripper assembly relative to the free end of the boom assembly.

FIG. 5 is a vertical cross-sectional view showing the details of the gripper assembly.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings and more particularly to FIG. 1, the principal components of the apparatus comprise an articulated two section boom assembly 10, a gripper assembly 12 connected to the free end of the boom assembly, and a movable supporting base 14 which in the illustrated embodiment is a fork truck.

Boom assembly 10 comprises a first section'formed by a pair of spaced parallel beams 16, and a second section formed by a hollow beam 18 which is pivotally connected to the outer ends of the beams 16 by a pin 20. The gripper assembly 12 is pivotally connected to the other end of the beam 18 by a pin 22.

A horizontal support plate 24 is attached to the base I4 and carries a fixed vertical spindle 26. A pivot block 28 is free to rotate about spindle 26. As best seen in FIG. 2, the pivot block 28 has a pair of slots 30 which receive the lower ends of the parallel beams 16. These beam ends are pivotally connected to pivot block 28 via bolt 32 and nut 34 to enable vertical adjustment of the boom assembly.

Movement of the boom assembly relatively to the base 14 in a horizontal direction is accomplished by a hydraulic motor 36 which rotates pivot block 28 about the spindle 26 by means of a sprocket 38 which engages a chain 40 which has its opposite ends connected to the pivot block by pins 42.

Vertical movement of the beams 16 relative to pivot block 28 is accomplished by a first hydraulic cylinder 44 which is pivotally connected at its rear end to an upstanding lug 46 on the pivot block 28 and at the other end its piston rod 48 is pivotally connected to an abutmerit block 50 which is welded to the parallel beams 16 approximately at their mid-points. Retraction of piston rod 48 by appropriate supply and removal of hydraulic fluid on opposite sides of the piston within hydraulic cylinder 44 will cause elevation of the boom assembly as a whole, and conversely extension of the piston rod will result in the boom assembly moving downwardly.

In similar fashion, a second hydraulic cylinder 52 is employed to pivot the second section of the boom assembly which comprises the hollow beam 18 relative to the first section of the boom assembly about pin 20. The hydraulic cylinder 52 is pinned at its rear end to the abutment block 50 and has a piston arm 54 pinned to the adjacent end 56 of the beam 18. Retraction of the piston rod 54 elevates the beam 18 and hence the gripper assembly 12 relative to the first boom section, and extension of the piston rod 54 depresses the gripper assembly and beam 18 relative to the parallel beams 16.

FIGS. 4 and illustrate the details of the gripper assembly. The attitude of the gripper assembly 12 relative to the adjacent or end of the beam 18 is adjusted by means of a chain and sprocket arrangement which is regulated by a third hydraulic cylinder 58. The piston arm of this hydraulic cylinder is connected to a clevis 60 which engages a link 62. The other end of link 62 is fixed to a sprocket 64 which is rotatable about bolt 32 and which is located within a slot 66 between the slots 30 in pivot block 28. An endless chain 68 is trained about the sprocket 64 at its lower end and is trained about a sprocket 70 which is disposed about pin at its other end. The sprocket 70 is fixed to the pin 20 as is an additional sprocket not shown in the illustrated view so that rotation is imparted to the additional sprocket about which is trained the upper end of an endless chain 72 which has its lower end trained about a sprocket 74 which is fixed to the pin 22. A preselected attitude of the gripper assembly is maintained during vertical movement of either or both of the boom sections by a parallel motion system which is known to those skilled in the art and hence is not fully herein described. Occasionally, the load to be grasped by the gripper assembly is packed near a ceiling or inside a box car, or is otherwise disposed so that it is not possible to grasp the load from above. In such instances, the attitude of the gripper assembly 12 is changed by actuation of the hydraulic cylinder 58 so that, for example, the load may be grasped from one side rather than from above.

Referring to FIG. 5, extending transverse to side walls 76 of the gripper assembly are a pair of coacting gripper arms comprising a pair of wedge shaped clamping bars 78 which have at their bases arcuate rubber inserts 80 constituting the load engaging surfaces with the left clamping bar being bolted to a pair of generally Z shaped links 82 and the right clamping bar being bolted to a pair of generally L shaped links 84. The arcuate configuration of surfaces and their treaded, resilient construction effects a firm tucking grip of the load, and this is particularly advantageous when engaging a so-called tobacco sheet which has an appearance similar to a loose sack of laundry. The links 82 and 84 are connected to gear segments 86 and 88 which are in toothed engagement and which are disposed upon shafts 90 and 92, respectively.

Each of the links 82 has at its upper end a clevis 94 which is pivotally connected to a one of a pair of links 96 which have a pin 98 fixed to their other ends. The pin 98 is also connected to the end of the piston rod of a fourth hydraulic cylinder 100 which reciprocates the pin 98 within slots 102 in the side walls 76.

Assuming that the gripper arms are in the position shown in full lines in FIG. 5, actuation of hydraulic cylinder 100 to push pin 98 downwardly within slots 102 causes the links 82 to move counterclockwise about shaft 90, thereby moving the left hand gripper arm toward the dash line position. At the same time, the right hand gripper arm is moved clockwise about shaft 92 in view of the toothed engagement of the gear segments 86 and 88. When the apparatus is being employed to grasp loads of tobacco as described above, the knots will normally be just above the abutting gripper arms shown in the article engaging position in dotted lines in FIG. 5. However, as indicated above, the invention is not limited to so gripping the load and is not limited to transporting loads of tobacco.

While the presently preferred embodiment of the invention has been shown and described with particularity, the invention is not limited to the precise structure of the illustrative embodiment. For example, the boom and gripper assemblies could be attached to any suitable platform, whether moble or stationary, for example, in lieu of the illustrated truck, these assemblies might be suspended from an overhead tramway or an under carriage tramway, or connected to other wheeled industrial vehicles. Also while hydraulic cylinders have been illustrated for activation of the articulated members, and are the presently preferred power source of the apparatus, it will be appreciated that other sources of power such as pneumatic cylinders and mechanical linkages might be utilized. It is intended to encompass all such modifications which may readily suggest themselvesto one of ordinary skill in the art upon being apprised of the present invention and which fall within the scope and spirit of the appended claims.

What is claimed is:

1. Article handling apparatus comprising a base, an articulated boom assembly having one end connected to said base and including a first boom section and a second boom section pivotally connected to each other, means to move said boom assembly as a whole about a vertical axis disposed upon said base, said first boom section including a pair of spaced parallel beamssaid second boom section comprising a hollow beam secured adjacent one end between the adjacent ends of said parallel beams, first piston means for moving said boom assembly as a whole relative to said base, second piston means having one end connected to said parallel beams and having a piston rod connected to one end of said hollow beam for moving said second boom section vertically relative to said first boom section, a first endless chain trained about a pair of sprockets including a drive sprocket, and disposed between said parallel beams, a second endless chain disposed within said hollow beam, sprocket means interconnecting said first and second endless chains for movement in unison, a sprocket fixed to said gripper assembly and rotated by said second endless chain, a gripper assembly including a pair of cooperating article engaging gripper arms pivotally connected to the outer end of said second boom section, a link connected to said drive sprocket to rotate said drive sprocket, and piston means connected to said link to impart rotation to said drive sprocket.

2. Apparatus according to claim 1, wherein said gripper assembly includes a pair of interengaged gear segments interconnecting said gripper arms to achieve correlated inward and outward movement of said gripper arms.

3. Apparatus according to claim 2, wherein said gripper assembly further comprises means defining a slot, piston means for reciprocating a pin within said slot, a link connected to said pin, one of said gripper arms having an end connected to said link, said gear segments having shafts connected thereto, said one gripper arm having an intermediate portion connected to one of said shafts so that upon movement of said pin means within said slot a corresponding movement is imparted to said one gripper am and to the associated shaft whereby the gear segments are rotated causing the other of said gripper arms to undergo a corresponding movement to that of said one gripper arm.

4. Apparatus according to claim 2, wherein each of said gripper arms has an arcuate resilient article engaging surface.

5. Apparatus according to claim 2, further comprising a hydraulic cylinder for actuating movement of said gripper arms.

6. Apparatus according to claim 1, wherein said means to move said boom assembly as a whole about a vertical axis includes a vertical spindle fixed to said base, a pivot block rotatable about said spindle, said pivot block having a pair of slots for reception of the lower ends of said parallel beams and having a slot for reception of said drive sprocket, said lower ends of said parallel beams and said drive sprocket spindle being mounted on a common shaft, a chain having its ends connected to opposite sides of said block, and a hydraulic motor having a sprocket engaging an intermediate portion of said chain. 

1. Article handling apparatus comprising a base, an articulated boom assembly having one end connected to said base and including a first boom section and a second boom section pivotally connected to each other, means to move said boom assembly as a whole about a vertical axis disposed upon said base, said first boom section including a pair of spaced parallel beams. said second boom section comprising a hollow beam secured adjacent one end between the adjacent ends of said parallel beams, first piston means for moving said boom assembly as a whole relative to said base, second piston means having one end connected to said parallel beams and having a piston rod connected to one end of said hollow beam for moving said second boom section vertically relative to said first boom section, a first endless chain trained about a pair of sprockets including a drive sprocket, and disposed between said parallel beams, a second endless chain disposed within said hollow beam, sprocket means interconnecting said first and second endless chains for movement in unison, a sprocket fixed to said gripper assembly and rotated by said second endless chain, a gripper assembly including a pair of cooperating article engaging gripper arms pivotally connected to the outer end of said second boom section, a link connected to said drive sprocket to rotate said drive sprocket, and piston means connected to said link to impart rotation to said drive sprocket.
 2. Apparatus according to claim 1, wherein said gripper assembly includes a pair of interengaged gear segments interconnecting said gripper arms to achieve correlated inward and outward movement of said gripper arms.
 3. Apparatus according to claim 2, wherein said gripper assembly further comprises means defining a slot, piston means for reciprocating a pin within said slot, a link connected to said pin, one of said gripper arms having an end connected to said Link, said gear segments having shafts connected thereto, said one gripper arm having an intermediate portion connected to one of said shafts so that upon movement of said pin means within said slot a corresponding movement is imparted to said one gripper arm and to the associated shaft whereby the gear segments are rotated causing the other of said gripper arms to undergo a corresponding movement to that of said one gripper arm.
 4. Apparatus according to claim 2, wherein each of said gripper arms has an arcuate resilient article engaging surface.
 5. Apparatus according to claim 2, further comprising a hydraulic cylinder for actuating movement of said gripper arms.
 6. Apparatus according to claim 1, wherein said means to move said boom assembly as a whole about a vertical axis includes a vertical spindle fixed to said base, a pivot block rotatable about said spindle, said pivot block having a pair of slots for reception of the lower ends of said parallel beams and having a slot for reception of said drive sprocket, said lower ends of said parallel beams and said drive sprocket spindle being mounted on a common shaft, a chain having its ends connected to opposite sides of said block, and a hydraulic motor having a sprocket engaging an intermediate portion of said chain. 